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View Full Version : Realflow vs. "Realflow for Lightwave"?



brainysmurf
06-22-2006, 03:46 PM
whats the difference between realflow (rf3) for USD 1995 at nextlimit.com, vs. the realflow for lightwave plugin at pluginz.com for USD 1080?

Thanks

Bog
06-22-2006, 05:08 PM
Let it go. Dynamite (http://www.cantarcan.com/v11/html/main.html) is out in a couple of weeks, and I can't think of a use I'd need RealFlow for in the face of it's partial-grid voxel math. For 195 Euros.

B'bye, 'Flow.

BazC
06-23-2006, 12:24 AM
Let it go. Dynamite (http://www.cantarcan.com/v11/html/main.html) is out in a couple of weeks, and I can't think of a use I'd need RealFlow for in the face of it's partial-grid voxel math. For 195 Euros.

B'bye, 'Flow.

Except Realflow does liquids and Dynamite doesn't (yet?), or have I missed something?

Bog
06-23-2006, 03:08 AM
Looking at the spec for v1.1, it says it does fluid dynamics type stuff? Even if it was a case of using it for detail-work on an otherwise HV or displaced geometry fluid-set.

Either way, Realflow seems fairly hugely priced unless you need *lots* of liquids IMHO. Your mileage, of course, may vary 'cause we all use these things in different ways.

hrgiger
06-23-2006, 03:13 AM
Dynamite does not do actual fluids in the traditional sense. It just creates more liquid volumetrics that are not possible with HV's.

Bog
06-23-2006, 03:19 AM
I ... I've failed you.

I've failed this forum.

I am... shamed.

RedBull
06-23-2006, 01:46 PM
I doubt there is any difference.
Usually retailers will sell it for less then the manufacturer.

Remember that Realflow 4, is meant to ship within the next month.
(June or July) So you may wish to hold off on buying Realflow3.

http://www.nextlimit.com/realflow/rf4/rf4.html

As for Dynamite, yeah it's not anywhere near the same league as Realflow.

loki74
06-23-2006, 04:29 PM
RF and Dynamite are like oranges and apples.

Firstly, and most obviously, RF is MUCH bigger and more capapble... as a result it is also much more expensive and difficult to use.

But from a technical perspective, they are also quite different. Dynamite uses a grid based volue tracking method--there is a 3D grid, and the volume and velocity of the fluid is sampled at each cell center. Particles are not invloved at all, except for in the advection term of the NSEs. But the point is, particles are not what you get out of the system. The advantage to this is that you can make very fine volumetric effects--smoke, dust, etc, very quickly. The downside is voxelization--when obsticles are turned into voxels in the 3D grid, they are like legos, and the result is that the fluid takes on a stair-stepped look at the interface between it and the object. Look a the flame/object example on the Dynamite site--you'll see this stair stepping when the flame hits the red objects. You can see literally what I mean in the voxelization of the race car.

RealFlow on the other hand, does not appear to use any grid-type structure. I do not know for sure, but I would assume that they either use a hybrid grid/particle model, in which some data is tracked on a grid, and other data on particles, or a fully particle implementation, such as Smoothed Particle Hydrodynamics. This is nice because we don't get any voxelization. However, at the same time, it is hard to track diffusive effects in gasses. It does provide a very nice means by which to generate a surface, making it very good for liquids and whatnot. (This is especially true given that Dynamite has yet to implement a liquid solver)

So heres what I'm saying in a nutshell--
Dynamite--good for gasses, beware of voxelization. Nice pricetag, probably simpler use... another plus is that it works within LW.

RF--good for liquids, but its much more pricey, more complicated to use. Although it is standanlone, it does play quite nicely with LW, as long as you remember to do certain things.

It is also important to note that RF does not only do fluid simulations--it does hardbody dynamics as well.

StereoMike
06-23-2006, 04:48 PM
If one want to play with grid based fluids, check out http://www.plasmapong.com/

It's free and the game has a sandbox mode to explore the technique.

Mike

Martin Adams
06-23-2006, 05:02 PM
Remember that Realflow 4, is meant to ship within the next month.
(June or July) So you may wish to hold off on buying Realflow3.


Correct me if I'm wrong, but if you buy Real Flow 3 now, you get a free upgrade to Real Flow 4 for only $1995.

But according to their web site, the full Real Flow 4 licence (Available in June 06), is $2700. So waiting would in theory cost an extra $705.

I'd be really intested in Real Flow, but its far too expensive for me at the moment and I don't have any particular uses for it.

I am of course on the lookout for a decent alternative. I wonder how easy it is to integrate the Blender fluid dynamics into LightWave...

loki74
06-23-2006, 05:07 PM
I am of course on the lookout for a decent alternative. I wonder how easy it is to integrate the Blender fluid dynamics into LightWave...

I've never done it before, but I have seen it done. I'm not entirely sure, but I believe a fellow named Jeremy Hardin looked into this, and put together some pretty nice tests... you might want to search the boards here and at spinquad

Martin Adams
06-23-2006, 05:12 PM
Yep, reading that post as we speak :D
http://www.newtek.com/forums/showthread.php?t=45593&highlight=blender+dynamics